½ tsp each hot chilli powder, garam masala and paprika (use ¼ tsp of each if you prefer a milder flavour)
¼ tsp turmeric
1 tsp each cumin and coriander seeds
½tsp fenugreek seeds
600g skinless, boneless chicken breasts, cut into 4cm chunks
2 tbsp rapeseed oil
2 onions, halved lengthways, sliced into rough, thin wedges
½tsp each paprika, turmeric and garam masala
¼ tsp hot chilli powder (leave this out if you'd prefer a milder flavour)
2 tbsp tomato puree
2 tbsp natural yogurt
250g basmati rice
200g frozen peas
handful coriander leaves, chopped
For the marinade, finely grate the ginger and garlic (you should have 1 rounded tbsp of each), then mix them together. Put half of this mix into a medium bowl, then stir in the yogurt, lime juice, chopped coriander, chilli, garam masala, paprika and turmeric. Heat a small heavy-based dry pan, tip in the cumin, coriander and fenugreek seeds, then heat briefly until toasted and smelling fragrant (they will start to jump in the pan). Remove and grind to a powder using a pestle and mortar. Stir half into the yogurt mix (save the rest for the sauce). Stir the chicken chunks into the spiced yogurt until well coated. Cover and leave to marinate for at least 30 mins, or overnight if you like.
Meanwhile, make the sauce. Heat the oil in a large pan. Add the onions, then fry over a medium heat for about 10 mins, stirring occasionally, until softened and turning brown. Stir in the remaining ginger and garlic, and stir-fry for 2 mins. Mix in the paprika, turmeric, garam masala, chilli and the rest of the toasted cumin, coriander and fenugreek. Cook for 1 min, stirring to scrape up the bits from the bottom of the pan. Stir in the tomato puree, then 150ml water. Cook for 1 min. Carefully transfer to a food processor or blender. Process to a thick, fairly smooth sauce. Return to the pan, pour in another 150ml water, then set aside. Can be made a day ahead. Soak the rice in cold water for up to 30 mins.
Heat the grill to high. Thread the chicken onto 8 wooden skewers (soaked first), then balance them across a baking tray lined with foil, so they are slightly raised over it. Grill for 12-15 mins until cooked and slightly charred around the edges. Meanwhile, drain the rice, then tip into a pan with 375ml water. Bring to a boil, then cook over a low heat, covered, for 8 mins. Remove from the heat but leave covered for 5 mins. Cook the peas in boiling water for 3 mins, drain. Fluff up the rice with a fork, then toss in the peas.
When ready to serve, reheat the sauce, stirring in any juices from the chicken and a drop more water to thin if necessary (it should be quite thick). Remove from the heat, stir in the yogurt, then season with a pinch of salt. Serve the chicken skewers with the rice, a scattering of coriander and lime wedges.